Big Blue is pushing hard to put enterprise collaboration software on smartphones and tablets powered by iOS, BlackBerry, and Android

Big Blue doesn't make a smartphone or a tablet, doesn't have its own mobile OS, and doesn't make glitzy commercials touting its mobile strategy. But IBM is quietly increasing its mobile footprint with offerings keyed to enterprise collaboration and a multiplatform strategy that features compatibility from devices running Apple's iOS, Research in Motion's BlackBerry, and Google's Android.

There's one other thing that IBM doesn't do these days: make and sell PCs. And that's one reason why its push for mobile devices is such a good strategic fit.

In a move that underlines its emphasis on mobile computing, IBM in January named veteran software exec Kevin Cavanaugh as vice president for business and technical strategy for IBM collaboration. Two-line titles on the business card aside, Cavanaugh says his real job is to "coordinate our mobile approach across individual products for collaboration. We need consistent strategy that crosses over from product to product." Customers, he told me in an interview this week, "don't want to think about switching products when working on a small device. They want it to be transparent."

Not surprisingly, Cavanaugh talked a lot about IBM's relationship with RIM and the recent BlackBerry World shindig, which he attended: "RIM has the biggest penetration in our customer base, so it is incredibly important to us. Apple is by culture more consumer-oriented, but we make up a key reference on their site. Android, though, is a little harder to figure out the 'who': Do we partner with the device makers or the Android team at Google?"

In a 45-minute discussion, Cavanaugh didn't mention Windows Phone even once. What he had to say about Microsoft had to do with the shift away from the old PC-centric computing paradigm -- not the software giant's attempts to gain traction in the mobile market.

Indeed a query I made after our discussion about running IBM mobile software on Windows Phone 7 or Hewlett-Packard's WebOS devices got the following politely damning response from a spokeswoman: "IBM provides mobile device support when it is in demand. Our customers are not asking us to provide support for the new Windows Phone, so we don't support that platform. The same holds true for HP. We have not seen enough demand. If that changes, we'll consider supporting the platforms."

The disappearing PCAlong with other InfoWorld colleagues, I've written about the consumerization of IT, and it's a trend that Cavanaugh sees as well. "The tablet is the best metaphor for that transformation ... and they are not running traditional PC operating systems," he says.

"But the format is a potentially a substitute for the PC in many cases. I've talked to CIOs who think they might be able to replace 20 percent of laptops with tablets over the next few years. So the hierarchy of Windows and Office that we accept as our environment will change," he says.

Cavanaugh himself carries an iPad when he travels, though he recently started using a RIM PlayBook as well. Despite his role as a mobile evangelist, Cavanaugh doesn't argue that no one need carry a PC: "If I'm traveling for two days, a tablet is fine. But three days and I'll carry a PC."

The switch to tablets, he says, is driven more by convenience than cost savings, since tablets can cost nearly as much as a midrange laptop. (Seeing an opportunity in that pricing, IBM Global Financing announced at BlackBerry World that it will offer low-interest leasing options for tablet computers regardless of manufacturer, a move aimed at increasing the penetration of tablets in the enterprise.)

It's not news that many IT execs are resistant to the use of tablets because of security concerns. But because the BlackBerry smartphone is so widely used in the enterprise, Cavanaugh figures that RIM's BlackBerry-tethered tablets will have a better reception than those running iOS or Android.

"The counterstory is that CIOs say, 'I don't want iPad in cause I don't think secure.'" And Android? "It's new as well, and yes, there are concerns. On the one hand, Android is more open [than Apple's iOS], so CIOs worry that you can put malicious stuff on it. On the other hand, a proactive CIO can put protection on it without waiting for Apple."

Cavanaugh is much too frank to pretend that iPads and Androids aren't making their way into the enterprise, and he notes that RIM just promised to extend its BES device management support to support those devices.

The push for social businessSocial business, says Cavanaugh, means using the data generated by messaging, email, IMs, microblogging, wikis, and so on to make enterprises more responsive and faster on their feet. IBM has pushed this concept for some time with offerings like IBM Connections. "What we want to do now is to present social business as completely as possible on mobile devices and we want it on multiple platforms -- Android, iOS, and BlackBerry. We'll do it with a mix of native apps and the use of the browser."

Connections now supports BlackBerry and Android, with native support for iOS and Android coming, according to a blog post by IBM's Chris Pepin. IBM's Lotus Notes Traveler software supports a variety of mobile devices with features that allow administrators to manage multiple devices and allow or deny access based on company security policies (using, ironically, Microsoft's Exchange ActiveSync protocol). Traveler can, for example, bar a jailbroken iPhone or one without encryption. Lotus Symphony is supported on BlackBerry and Android, although it does not yet run on iOS.

The mobile push also encompasses development tools, which can now be used to make custom apps run on mobile devices, a signficiant priority for IBM's customers, says Cavanaugh.

San Francisco journalist Bill Snyder writes frequently about business and technology. He writes the Tech's Bottom Line blog for InfoWorld, and his work appears regularly in CIO.com and the publications of Stanford's Graduate School of Business and the Haas School of Business at the University of California at Berkeley.